[GHC] #14737: Improve performance of Simplify.simplCast

[GHC]

#14737: Improve performance of Simplify.simplCast
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        Reporter:  tdammers          |                Owner:  (none)
            Type:  bug               |               Status:  patch
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.2.2
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Compile-time      |  Unknown/Multiple
  performance bug                    |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #11735 #14683     |  Differential Rev(s):  Phab:D4385
       Wiki Page:                    |
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Comment (by goldfire):

 Yes, I think Simon's comment:10 is correct. Try removing that.

 Note that Phab:D4395 currently removes the `piResultTy` from that case,
 but it's quite possible that the `eqType` call is what's taking up the
 time.

 You might also try removing the similar clause from `pushCoValArg`.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14737#comment:11>
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